Vibrating spray apparatus and method of spraying

ABSTRACT

A vibrating spray apparatus and method of spraying which produces a spray pattern of substantial uniform density, the spray apparatus including a spray tube that is free at one of its ends, means to supply liquid to the spray tube from the other end thereof, a motion transmitting device associated with the spray tube to impart vibrations of sufficient magnitude to the spray tube to cause the free end of the tube to move in an orbital path. The method of the present invention involves the movement of a stream of liquid in an orbital path wherein the liquid is discharged while moving in the orbital path to produce a pattern of uniform density.

United States Patent Waldrum VIBRATING SPRAY APPARATUS AND METHOD OFSPRAYING John E. Waldrum, Ambler, Pa.

Amchem Products, Inc., Ambler, Pa.

May 28, 1970 Inventor:

Assignee:

Filed:

Appl. No.:

References Cited UNITED STATES PATENTS FOREIGN PATENTS OR APPLICATIONS132,977 11/1947 Australia ..239/229 Primary ExaminerLloyd L. KingAttorney-Caesar, Rivise, Bernstein & Cohen [5 7] ABSTRACT A vibratingspray apparatus and method of spraying which produces a spray pattern ofsubstantial uniform density, the sprayapparatus including a spray tubethat is free at one of its ends, means to supply liquid to the spraytube from the other end thereof, a motion transmitting device associatedwith the spray tube to impart vibrations of sufficient magnitude to thespray tube to cause the free end of the tube to move in an orbital path.The method of the present invention involves the movement of a stream ofliquid in an orbital path wherein the liquid is discharged while movingin the orbital path to produce a pattern of uniform density.

9 Claims, S-Drawing Figures PATENTEDAPR 41972 3, 653 598 3 INVENTOR IJOHN 5. WALDRUM ATTORNEYS.

VIBRATING SPRAY APPARATUS AND METHOD OF SPRAYING This invention relatesto a vibrating spray apparatus and method of spraying and has as itsobjective the provision of a new and improved device of this generalclass as well as a significant method to achieve amazingly uniformspraying in agricultural and other fields.

There are many spray operations wherein the achievement of a uniformspray is most desirable. Many liquids are sprayed in very dilute form,since in this way minor variations in spray rate are quite insignificantin view of large volumes being handled. However, spraying in largevolumes necessitates a supply of large volumes of a diluent like water,and the handling thereof could require a considerable capitalinvestment. Furthermore, there are many substances which are eitherpartially or wholly insoluble in water,.but instead are soluble only inorganic solvents which are more expensive than water, and clearlyuneconomical to use in large volumes.

Accordingly, it has been suggested that spraying of concentrated liquidsbe attempted. However, here relatively minor variations in the spraypattern can be quite significant. A seemingly slight increase in sprayrate of a concentrated liquid could result in an overdosage and waste,and a slight decrease in spray rate could result in an ineffectiveamount of active ingredient being applied to the target area.

Another advantage inherent in spraying concentrated liquids is that avery small volume will almost necessarily produce a lower total amountof fine droplets (less than 400 microns in diameter), and this willminimize drift of spray droplets that is caused by drafts and windwhereas in high volume spraying a large number of fine droplets isusually produced. Also, where a droplet is produced having a sizegreater than 2,000 microns in diameter, it normally will subdivide intoa primary droplet and a satellite droplet, with the latter usually beinga fine droplet.

The problem is spraying of concentrated liquids to assure uniformity hasbeen solved by an apparatus disclosed and claimed in co-pendingapplication Ser. No. 8,581. However, it was believed desirable that aspray apparatus be provided with even a small number of moving parts.

Accordingly, it is an object of the present invention to provide aliquid spray device which is relatively simple and inexpensive tomanufacture in view of its small number of moving parts. Still anotherobject of this invention is to provide a spray device that producesstable droplets (between 400 and 2,000 microns in diameter).

Another object of the present invention is to provide a liquid spraydevice including an elongated spray tube fixedly mounted at one end andfree at the other wherein a restricted outlet is provided, said tubebeing associated with motion transmitting means capable of imposingvibrations on the free end of the tube of a magnitude and in a directionsufficient to cause the free end of the tube to move in an orbital pathwhereby liquid supplied to and passing through said tube is broken intodiscrete particles as it is emitted therefrom through the restrictedoutlet and is thrown outwardly thereof in a generally uniform,curvilinear pattern by the movement of said tube.

In carrying out the above object, it is a further object to use aplurality of orifices at the free end of said tube as means for formingsaid restricted outlet, wherein the number, size and direction thereofis used to control the shape and size of the spray pattern, all otherfactors remaining constant.

Another object of the invention is to provide means for orbitting thetube that is positioned remote therefrom whereby the tube is subjectedto little or no wear.

Another object is to dispose the spray tube in a generally verticalposition with respect to its major axis whereby the spray emittedtherefrom is directed downwardly in an expanding pattern of greatuniformity and under close control whereby spraying operations may begenerally improved.

A still further object of the invention is to provide a method forproducing a curvilinear spray pattern wherein an elongated spray tube isprovided which is fixedly mounted atone end and free at the other end;the tube being caused to gyrate by means acting adjacent the fixed endthereof whereby the free end describes an orbital path. Liquid suppliedto the tube and passing outwardly from the free end thereof is brokeninto substantially uniform particles that are thrown outwardly in anexpanding curvilinear pattern, the shape, size and direction of which iscontrolled, within limits, by the rate of vibrations imparted to saidtube and the design of the free end of said tube.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accom panying drawings wherein:

FIG. 1 is a perspective view of a spray apparatus embodying the presentinvention, with certain portions cut away and certain other portionsshown in section in order to reveal internal portions of the device;

FIG. 2 is a sectional view taken along the lines 22 of FIG.

FIG. 3 is an enlarged sectional view taken along the lines 3-3 of FIG.1;

FIG. 4 is a greatly enlarged sectional view of the free end of the spraytube shown in FIG. 1 in actual rotation in an orbital path, and showinga second position of the end of the spray tube; and

FIG. 5 is a view taken along the lines 5-5 of FIG. 4.

Referring to the drawings and particularly FIG. 1, an improved spraydevice 20 is shown. This device may be formed from any suitable materialthat is resistant to the liquid to be sprayed and which has sufficientstrength to be useful over extended periods of time, this material is amatter of choice and forms no part of this invention. In one embodiment,the entire device, except for some moving parts, is molded from apolycarbonate plastic.

The device 20 includes a liquid reservoir 22 at the upper end thereofwhich is cylindrical in cross section and which is closed at its upperend by cover 24. The cover 24 carries an inlet 26 and an overflow andair vent 28 therein. The inlet 26 is connected to any suitable source ofliquid by means of conduit 30.

The inlet 26 is preferably formed from a tubular metal insert 32 pressedinto the cover 24.

Within the reservoir 22 is contained a float 40 which is a hollowcylindrical member that is dimensioned so as to control the amount ofliquid admitted to said reservoir 22. When the liquid level rises to adesired point, the float moves upwardly to cause a valve (not shown) toclose and prevent further liquid to enter. As the float movesdownwardly, the valve opens. A protuberance 42 is provided at the bottomof the reservoir 22 to prevent the float 40 closing off an outletpassage 44 from the reservoir. This outlet 44 connects with an elongatedstandpipe 46 that carries a flexible, liquid spray device 48 at itslower extremity. This device 48 includes several important details andcontrols that will be described in detail hereinafter.

A pair of supports, 50 and 52 may be molded on or attached to thestandpipe 46 and these carry the remainder of the mechanism of thedevice 20. Support 50 extends outwardly and normal to the standpipe 46and supports a small motor 54. This motor 54 is a commercially availabledevice (see U.S. Pat. No. 2,842,692) and forms no part of my invention.The motor 54 is fixedly positioned on the support bracket 50 which isbifurcated so that the motor may be easily inserted and removed.

The lower bracket 52 is also bifurcated but in the opposite directionwhereby two arms 56 and 58 are formed, their functions will be describedlater. The motor 54 is connected to a shaft 60 through a shock absorbingconnection 62. This consists merely of a rubber-like sleeve thatembraces the motor shaft at one end and the drive shaft 60 at the other.

The lower end of shaft 60 connects through a second shock absorbingmember 64 with a shaft 66. This shaft 66 passes through the arm 56 andis joumalled thereby and is also journalled in the arm 58. Between thearms 56 and 58 and fixedly positioned on the shaft 66 is a weight 68.This weight 68 is mounted off-center with respect to the shaft 66whereby during rotation of the shaft 66, the weight 68 causes vibrationof the device. This vibration is controlled with respect to the motor 54and its bearings (not shown) by means of the two shock absorbingconnections 62 and 64 and suffers little transmission of the vibrationcaused by the off-center weight 68, certainly not enough to cause anyharm.

The off-center weight 68 is the means for imparting vibrations to thestandpipe 46 which carries the spray device 48 at its lower extremity.It will be noted that the upper end of the device 48 is fixedly mountedto the standpipe 46 but that the lower end thereof is free andunsupported. When the motor 54 causes the off-center weight 68 torotate, vibrations are set up in the standpipe 46, particularly in thelower end thereof. These vibrations, because of the way they areinduced, create an orbital movement that is imperceptible within thestandpipe 46 but which is amplified as it reaches the free end of thespray tube 48 causing it to gyrate in an orbit of curvilinear extent.When liquid passes downwardly through the standpipe 46 and outwardlyfrom the free end 70 of the spray tube 48, the liquid is dispersed intouniform particles to form a spray that has an expanding curvilinearpattern. By controlling the shape, size and direction of the open end 70of the tube 48 and by controlling the speed of the motor and the extentof vibra tion caused by the weight (which may be varied as desired) itis possible to obtain a wide variety of patterns of varying extent aswell as affecting control of size of the spray particles.

Specifically, with the motor 44 operating free at from 10,000 to 12,000RPM and using a polyethylene spray tube 48 having a free and unsupportedlength of 1% inches, an outer diameter of three-sixteenths of an inchand a bore of oneeighth of an inch, that the motor speed was reduced to1,200 to 1,500 RPM when a aqueous vehicle was being sprayed through aterminal nozzle on the tube 48 having four orifices each of 0.017 inchesin diameter. In this instance, the vibrations were caused by a brassweight one-half inch long, threeeighths of an inch in diameter andpositioned with its axis oneeighth inch off center. The reduction ofmotor speed was caused by the load imposed by the resonant frequencyinduced by the spray tube gyrations. Obviously, these figures willchange widely with different terminal orifices, lengths of tube 48,different off-center weights 68, different placements thereof andvarying motor speed, etc., and the above figures are only given asexemplary of one workable embodiment of the device.

Again referring to the drawings, FIGS. 3 and 4 are offered to showvarious details of the spray tube 48. In FIG. 3 an enlarged sectionalview is depicted wherein a check valve 70 is used which prevent leakagewhen the device is inactive. The valve 70 includes an elastomeric seat72 consisting of an O ring seated in the base of a tubular extension 74which is closed by gravity by a ball bearing 76 when the device isinactive. As shown in FIG. 3 tubular extension 74 ends in a nipple 73Athat is slipped within upstream end 73B of tube 48. The downstream end81A of tube 48 receives plug 81.

Upon energization of the motor 54 and the resulting induced vibrations,the ball 76 rises and opens the valve 70 whereby liquid may flowdownwardly to the end of the tube 48. In the specific embodimentdisclosed, the tube 48 includes a plug 81 with several identicalrestricted orifices or passages 80 at the free end thereof. It will benoted that these are each bent outwardly a small amount and this acts toincrease the extent of the spray pattern. It is apparent that many suchdeviations in design may be used to alter the type, extent and shape ofpattern. It will be discovered that desired results may best beaccomplished through trial with limited experimentation for any specificapplication of the device.

FIG. 4 shows in dotted lines the positions assumed by the tube 48 whenthe device is in operation. Another limit is depicted in dotted lines at82. FIG. 5 is offered to show that the orbit 84 of the tube 48 is ofgenerally circular extent although it is apparent that it may also beelliptical, if desired. It is also possible to oscillate the tube 48through suitable modification. However, more energy is absorbed in thisinstance due to the cyclic changes in direction of the tube 48. Such anenergy loss does not occur when using orbital movement since thedirection of movement is always the same.

If desired, an outer cover (not shown) may be used. The cover may beprovided with bayonet slots which cooperate with protuberances on thelower portion of the reservoir 22. In the instant case, theseprotuberances are formed by collars that project and protect the powerlines for the motor 54. The cover in this form is easily attached ordetached as desired.

It is apparent that in place of plastic, the device of this inventionmay be formed by die-casting, machining or built up from a plurality ofparts made from metal, plastic or a combination thereof. The inventionis in no way limited to specific materials or constructions but isbroadly directed to a novel and inexpensive way to obtain an orbitalmovement of a spray tube which in turn affects a controlled atomizationand distribution of liquid particles.

When the device is used for agricultural pursuits, it may be useful toprovide a dust boot or cover (not shown) which may be slipped over thecollar 71. Such a shield, if resilient, will in no way affect thegyrations of the tube 48 but will prevent dust from affecting the movingparts of the exciting mechanism. In this same connection, it is obviousthat a flexible spray tube 48 (as shown) has many advantages inagricultural applications. When the spray device is positioned ratherclose to the ground, the flexible tube may flex when clearance isinsufficient to pass vegetation, for example. Such flexing does notaffect operation nor does it harm the tube or nozzles. Further, the useof replaceable nozzles or orifices is highly useful since the quantityand type of spray pattern may be modified by simply changing saidnozzles.

One additional matter that bears amplification concerns the spray tube48. In this disclosure, the tube 48 has been disclosed as being formedfrom a flexible plastic material. On the other hand, it may befabricated from a relatively non-flexible plastic or from metal, ifdesired. In this instance, the orbital movement of the free end of thetube will not be as great when exposed to the same exciting force.However, lengthening of the tube and or increasing the exciting force(by greater vibration or increased frequency or both) will improve theextent of the orbital path and it is believed that the exercise of thesechanges is clearly within the purview of persons skilled in the art.

While the device as disclosed is limited to a generally verticalapplication due to gravity flow of the liquid to be sprayed, it isapparent that the same may be positioned in any desired manner, due todisposition or desire, and if the gravity feed is not practical, that apressure feed may be used while still enjoying themany advantages of thedevice.

It can be seen from the foregoing that with the apparatus of the presentinvention the spray tube is caused to rotate about an axis by avibrating source of energy, rather than a turning force. In view of theexcellent spray patterns achieved with the apparatus of the presentinvention, small quantities of concentrated liquid, such as 1 pint peracre, can be precisely and evenly applied to a target area. It is to benoted that the apparatus of the present invention can handle liquidsother than solutions, such as suspensions, and can handle liquids havinga wide range of viscosities.

Yet in view of all the foregoing, the present invention is relativelycompact and inexpensive. Furthermore, with the present invention thepattern can be made to be dense in the center or dense on the outside oruniform throughout.

Without further elaboration, the foregoing will so fully il1ustrate myinvention, that others may, by applying current or future knowledge,readily adapt the same for use under various conditions of service' Whatis claimed as the invention is:

1. A liquid spray device adapted to produce a spray of substantiallyuniform density having a generally curvilinear pattern, comprising incombination: an elongated flexible spray tube fixedly mounted at one endand free at the other end and having a restricted outlet at said freeend thereof; liquid supply means connected to said tube adjacent saidfixed end and adapted to supply liquid thereto to be sprayed from saidoutlet; and a motion transmitting device associated with said tube andadapted to impart vibrations thereto at a resonant frequency in adirection and of sufficient magnitude to cause the outlet end of saidtube to describe an orbital path about a fixed stationary axis throughthe fixed end of said spray tube whereby liquid being emitted from saidoutlet is thrown outwardly in the form of discrete particles to producea predetermined curvilinear spray pattern.

2. The device claimed in claim 1 wherein the restricted outlet consistsof at least two orifices.

3. The device claimed in claim 2 wherein at least a portion of saidspray tube adjacent said free end is flexible.

4. A liquid spray device adapted to produce a spray having asubstantially uniform density and of a generally circular pattern,comprising in combination: a generally perpendicularly disposed,elongated, flexible spray tube fixedly mounted at the inlet end thereofand free at the outlet end; liquid supply means connected to said tubeadjacent the fixed end thereof and adapted to supply liquid thereto tobe sprayed from said outlet; and a motion producing device associatedwith said tube and adapted to impart vibrations thereto at a resonantfrequency in a direction and with sufficient magnitude to cause theoutlet end of said tube to move in a generally circular orbital pathabout a fixed stationary axis through the fixed end of the spray tubewhereby liquid being emitted from said outlet is thrown therefrom in theform of discrete particles to produce a predetermined circular spraypattern.

5. The device claimed in claim 4 wherein said restricted outlet consistsof at least two separate small diameter orifices.

6. The device claimed in claim 5 wherein said restricted outlet consistsof four separate small diameter tubes each bent slightly adjacent theends thereof so as to be non-parallel with the major axis of the device.

7. The device claimed in claim 4 wherein said motion producing device ismounted outside the vertical axis of said spray tube and consists of arotating off-center weight.

8. The device claimed in claim 4 including a motor and offcenter weightwhich are positioned in misalignment with the axis of said tube.

9. A liquid spray device adapted to produce a spray having asubstantially uniform density and of a generally circular pattern,comprising in combination: a generally perpendicularly disposed,elongated flexible spray tube fixedly mounted at the inlet end thereofand free at the outlet end; liquid supply means connected to said tubeadjacent the fixed end thereof and adapted to supply liquid thereto tobe sprayed from said outlet; and a motion producing device associatedwith said tube and adapted to impart vibrations thereto at a resonantfrequency in a direction and with sufficient magnitude to cause theoutlet end of said tube to move in a generally circular orbital pathabout a fixed stationary axis through the fixed end of the spray tubewhereby liquid being emitted from said outlet is thrown therefrom in theform of discrete particles to produce a predetermined circular spraypattern, valve means being provided adjacent the device wherein valvemeans are provided adjacent the fixedly mounted end of the spray tube,said valve means being sensitive to said vibrations to remain open forpermitting liquid flow therethrough and closing only when saidvibrations cease to prevent such flow.

1. A liquid spray device adapted to produce a spray of substantiallyuniform density having a generally curvilinear pattern, comprising incombination: an elongated flexible spray tube fixedly mounted at one endand free at the other end and having a restricted outlet at said freeend thereof; liquid supply means connected to said tube adjacent saidfixed end and adapted to supply liquid thereto to be sprayed from saidoutlet; and a motion transmitting device associated with said tube andadapted to impart vibrations thereto at a resonant frequency in adirection and of sufficient magnitude to cause the outlet end of saidtube to describe an orbital path about a fixed stationary axis throughthe fixed end of said spray tube whereby liquid being emitted from saidoutlet is thrown outwardly in the form of discrete particles to producea predetermined curvilinear spray pattern.
 2. The device claimed inclaim 1 wherein the restricted outlet consists of at least two orifices.3. The device claimed in claim 2 wherein at least a portion of saidspray tube adjacent said free end is flexible.
 4. A liquid spray deviceadapted to produce a spray having a substantially uniform density and ofa generally circular pattern, comprising in combination: a generallyperpendicularly disposed, elongated, flexible spray tube fixedly mountedat the inlet end thereof and free at the outlet end; liquid supply meansconnected to said tube adjacent the fixed end thereof and adapted tosupply liquid thereto to be sprayed from said outlet; and a motionproducing device associated with said tube and adapted to impartvibrations thereto at a resonant frequency in a direction and withsufficient magnitude to cause the outlet end of said tube to move in agenerally circular orbital path about a fixed stationary axis throughthe fixed end of the spray tube whereby liquid being emitted from saidoutlet is tHrown therefrom in the form of discrete particles to producea predetermined circular spray pattern.
 5. The device claimed in claim 4wherein said restricted outlet consists of at least two separate smalldiameter orifices.
 6. The device claimed in claim 5 wherein saidrestricted outlet consists of four separate small diameter tubes eachbent slightly adjacent the ends thereof so as to be non-parallel withthe major axis of the device.
 7. The device claimed in claim 4 whereinsaid motion producing device is mounted outside the vertical axis ofsaid spray tube and consists of a rotating off-center weight.
 8. Thedevice claimed in claim 4 including a motor and off-center weight whichare positioned in misalignment with the axis of said tube.
 9. A liquidspray device adapted to produce a spray having a substantially uniformdensity and of a generally circular pattern, comprising in combination:a generally perpendicularly disposed, elongated flexible spray tubefixedly mounted at the inlet end thereof and free at the outlet end;liquid supply means connected to said tube adjacent the fixed endthereof and adapted to supply liquid thereto to be sprayed from saidoutlet; and a motion producing device associated with said tube andadapted to impart vibrations thereto at a resonant frequency in adirection and with sufficient magnitude to cause the outlet end of saidtube to move in a generally circular orbital path about a fixedstationary axis through the fixed end of the spray tube whereby liquidbeing emitted from said outlet is thrown therefrom in the form ofdiscrete particles to produce a predetermined circular spray pattern,valve means being provided adjacent the device wherein valve means areprovided adjacent the fixedly mounted end of the spray tube, said valvemeans being sensitive to said vibrations to remain open for permittingliquid flow therethrough and closing only when said vibrations cease toprevent such flow.